<?php

namespace Tests\Unit\Services;

use App\Services\VatIdService;
use Tests\TestCase;

class VatIdServiceTest extends TestCase
{
    private VatIdService $service;

    protected function setUp(): void
    {
        parent::setUp();
        $this->service = new VatIdService;
    }

    /** @test */
    public function it_normalizes_vat_ids()
    {
        $this->assertEquals('ATU12345678', $this->service->normalize(' at-u 12.345,678 '));
        $this->assertEquals('', $this->service->normalize(null));
    }

    /** @test */
    public function it_extracts_country_code_from_prefix()
    {
        $this->assertEquals('AT', $this->service->extractCountryCode('ATU12345678'));
        $this->assertEquals('ES', $this->service->extractCountryCode('ESY9284953M'));

        // Kein EU-Präfix -> Fallback auf Account-Land
        $this->assertEquals('AT', $this->service->extractCountryCode('53618009', 'AT'));
        $this->assertNull($this->service->extractCountryCode('53618009', 'CH'));
    }

    /** @test */
    public function it_checks_plausible_format()
    {
        $this->assertTrue($this->service->isPlausibleFormat('ATU12345678'));
        $this->assertTrue($this->service->isPlausibleFormat('DE123456789'));
        $this->assertTrue($this->service->isPlausibleFormat('ESY9284953M'));

        // Nur Ziffern ohne Länderpräfix (z.B. österreichische Steuernummer)
        $this->assertFalse($this->service->isPlausibleFormat('53618009'));
        // Kein EU-Ländercode
        $this->assertFalse($this->service->isPlausibleFormat('CH123456789'));
        $this->assertFalse($this->service->isPlausibleFormat(''));
        $this->assertFalse($this->service->isPlausibleFormat(null));
    }

    /** @test */
    public function german_vat_ids_never_qualify_for_reverse_charge()
    {
        $this->assertFalse($this->service->qualifiesForReverseCharge('DE123456789'));
        $this->assertFalse($this->service->qualifiesForReverseCharge('de 123 456 789'));
        $this->assertTrue($this->service->qualifiesForReverseCharge('ATU12345678'));
        $this->assertFalse($this->service->qualifiesForReverseCharge('53618009'));
        $this->assertFalse($this->service->qualifiesForReverseCharge(null));
    }

    /** @test */
    public function vies_check_returns_invalid_for_implausible_ids_without_api_call()
    {
        $this->assertEquals(VatIdService::CHECK_INVALID, $this->service->checkVies('53618009'));
        $this->assertEquals(VatIdService::CHECK_INVALID, $this->service->checkViesCached(''));
    }

    /** @test */
    public function vies_check_returns_unavailable_when_disabled()
    {
        config(['services.vies.enabled' => false]);

        $this->assertEquals(VatIdService::CHECK_UNAVAILABLE, $this->service->checkVies('ATU12345678'));
    }
}